This is a simple parser generator based on the Parsing Expression Grammar formalism.
Run peg input_file.rustpeg to compile a grammar and generate Rust code on stdout.
```
rule_name -> type = expression ```
If a rule is marked with #[pub], the generated module has a public function that begins parsing at that rule.
. - match any single character"literal" - match a literal string[a-z] - match a single character from a set[^a-z] - match a single character not in a setrule - match a production defined elsewhere in the grammar and return its resultexpression* - Match zero or more repetitions of expression and return the results as a Vecexpression+ - Match one or more repetitions of expression and return the results as a Vecexpression? - Match one or zero repetitions of expression. Returns an Option&expression - Match only if expression matches at this position, without consuming any characters!expression - Match only if expression does not match at this position, without consuming any charactersexpression ** delim - Match zero or more repetitions of expression delimited with delim and return the results as a Vecexpression ++ delim - Match one or more repetitions of expression delimited with delim and return the results as a Vece1 / e2 / e3 - Try to match e1. If the match succeeds, return its result, otherwise try e2, and so on.e1 e2 e3 - Match expressions in sequence
a:e1 b:e2 c:e3 { rust } - Match e1, e2, e3 in sequence. If they match successfully, run the Rust code in the action and return its result. The variables before the colons in the preceding sequence are bound to the results of the corresponding expressionsMatch actions can extract data from the match using these variables:
&str slice. Examples:
name -> String
= [a-zA-Z0-9_]+ { match_str.to_string() }
number -> int
= [0-9]+ { from_str::<uint>(match_str).unwrap() }